BIDIR or INOUT Primitive/Port

AHDL Syntax:

io : BIDIR;

Verilog HDL Example Instantiation:

inout io

VHDL Syntax:

io : INOUT

Source:

TRI or OPNDRN

Destination:

Device I/O pin

If TRI is disabled, external input is allowed. If TRI is enabled and an external signal is applied, signal contention is possible and could damage the device.

In a Block Design File (.bdf) Definition, you can use the Pin Properties dialog box to specify pin properties for this primitive, such as the pin name and default value.

Note:
  • Only the pin assignments of the top-level entity are used during compilation.
  • For information about primitive instantiation, go to Using a Logic Function.
Related reference

TRI Primitive
OPNDRN Primitive
Pin Properties Dialog Box

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